Adding Audiotrack to mkv confusion

[Xan]

Hi,
I have MKV with HEVC Video one AC3 Audiotrack and some Subtitletracks which works just fine with VLC Player.
Than I have a seperate AC3 Track which also works with VLC.
When I put them together with XMediaRecode whitout converting anything (setting everything on copy), the addet AC3 Track is suddenly silent in VLC but it does work with the default Windows 10 Videoplayer. That just can't play the HEVC Video.
Now I take that Video and Repack it with Avidemux, again everything just set to copy, and suddenly everything works in VLC.
But Avidemux gets rid of the Subtitles.

Can anybody explain what is going on here? I'm confused

[netmask56]

For MKV files use MKVToolNix (this is the correct tool to use with MKV fies) to add your AC3 audio track. If you want to make it the default track just mark it default in MKVToolNix. Simple!

[Xan]

Oops. I have that, but forgot about it. Don't need it very often. Thanks
It would still be interesting to know why it didn't work with XMediaRecode, because I see no reason why it shouldn't.

[netmask56]

I don't know anything about XMediaRecode but as the name suggests it possibly re-encodes? MKVToolNix doesn't re-encode and is not capable of doing so. It's quick and it works. It simply remuxes the elements selected.

[netmask56]

Don't forget if you have 2 audio tracks, or more, in your MKV file you need to indicate which one is the default track so your media player of choice selects that track. You can do this simply in MKVToolNix via a drop down menu. Maybe XRecode doesn't have this ability?